Stripe applicator for pavements



Jan. 30, 1962 c. E. SEARIGHT 3,018,

STRIPE APPLICATOR FOR PAVEMENTS Filed Dec. 15, 1958 2 Sheets-Sheet 1INVENTOR.

CHARLES E. SEARIGHT TTORNEY Jan. 30, 1962 c. E. SEARIGHT 3,018,704

STRIPE APPLICATOR FOR PAVEMENTS Filed Dec. 15, 1958 2 Sheets-Shet 2INVENTOR. CHARLES E. SEARIGHT ATTQRNE This invention relates to pavementstripe applicators and, more particularly, to a machine for applying astripe of hot thermo-plastic material to a roadway. This application isa continuation-in-part of my co-pending application Serial No. 604,989,filed August 20, 1956, for Apparatus for Applying Thermo-plastic Markersto Roadways, now Patent No. 2,875,675.

In applying a stripe of thermoplastic material along a roadway, thematerial was previously dispensed from the bottom of a heated tankthrough an outlet valve and thence directly onto the roadway. In myco-pending application, supra, there isshown an unique burnerarrangement, one burner for blasting a flame onto the roadwayimmediately in front of where the material is applied so that thematerial along the bottom of the stripe will not freeze too quickly andthus bridge over cracks and crevices in the pavement surface, andanother burner for blasting a flame over the outlet valve so that thematerial wont thicken or freeze in the valve. The object now is toprovide a road striper wherein hot thermoplastic stream is dispensedfrom a heated tank through I an outlet valve into a chute, and thenceonto the roadway through a shoe. One of the objects is to control theoutflow of striping material from the shoe, and also to arch the top ofthe stripe as it flows onto the roadway. To this end it is intended toprovide a combined adjustable shoe gate and doctor blade. Anotherfeature is the mounting of the chute so that it can be raised andlowered from the roadway. On the machine immediately behind the shoe ismounted a dispenser for sprinkling tiny glass beads on the then stilltacky surface of the freezing stripe, the dispenser being driven by aground-engaging wheel. A further object of the invention is to provide acombined manual control linkage for the chute, shoe gate and the powerdrive for the bead dispenser so that whenever the chute is lowered,

, the dispenser ground wheel will be clutched against the engagingdispenser wheel are simultaneously lifted. By

these sequences of activating and de-activating the parts, completesprinkling of the stripe with beads, from start i to finish, is assured.

Another of the objects is the provision of a heater for directly heatingthe dispensing apparatus leading from the tank bottom to the ground, andfor indirectly heating the material flowing therethrough. Accordingly,it is now proposed to provide a radiant heater, constantly operated,disposed to impinge its rays onto the dispensing valve at the bottom ofthe tank, onto the chute leading downwardly therefrom, and onto the shoeand combined shoe gate and doctor blade. Thus, all the dispensingapparatus will be pre-heated and kept hot, and the material itself iskept hot as it flows down the chute and out through the shoe.

Still another object is to ensure that the roadway immediately in frontof the point of application of the stripe will always be pre-heatedwhenever the gate valve, which controls the flow of thermoplasticmaterial from the chute onto the roadway, is opened. Likewise, since the3,fl18,7fl4 Patented Jan. 30, 1962 roadway pre-heating burner blasts outa comparatively large flame, it is intended to save fuel by shutting itoff whenever the gate valve is closed. The common control linkage forthe roadway pre-heating burner and the gate valve also provides a safetyfactor which avoids accidental fire-setting, in that the pre-heatingblast is started only when the material flows on the roadway.

These and other objects will be apparent from the followingspecification and drawings, in which:

FIGURE 1 is a side elevation of the applicator;

FIGURE 2 is a plan view of the applicator;

FIGURE 3 is a fragmentary view, showing in side elevation the dispensingvalve, chute, combined chute gate and doctor blade and parts of theoperating linkages therefor;

FIGURE 4 is a fragmentary plan view of the parts shown in FIGURE 3;

FIGURE 5 is a fragmentary cross section along the a line 5-5 of FIGURE3; and,

FIGURE 6 is a fragmentary rear elevation of the bead dispenser as seenalong the line 66 of FIG. 1.

Referring now to the drawings, in which like reference numerals denotesimilar elements, the stripe applicator 2 has a sheet metal casing 4supported on two nonswiveling forward wheels 6 and a non-swiveling rearwheel 7 so that the applicator maintains a generally straight coursewhen trundled along a roadway R. The applicator may be tipped forwardlyso that it rests on the two forward Wheels 6 and a pair of raisedrollers 8 at the front of casing 4, the relatively short wheel base thenpermitting a sharp angle turn. Ordinarily, the flow of striping materialis cut off when the machine is tipped forwardly but, when a misalignedsegment of the road, such as a gutter pan, is encountered, rollers 8 maybe used for supporting the machine while laying the last few inches ofstripe prior to cut off.

A material supply tank 10 is housed within casing 4 and a pressure typetank burner, not shown, is provided for keeping the stripe material hot,in a thick liquid state. The tank burner is supplied with gas from atank housed in a fuel compartment 12 in the rear of easing 4. Also fedwith gas from the fuel compartments are a pro-heating burner 14 which,when on, blasts a flame downwardly onto the roadway R, and a radiantheater 16, normally on, and disposed to project its rays onto thematerial dispensing mechanism detailed hereinbelow. The temperature ofmaterial within the supply tank is indicated on a gauge 18 and fuelvalves 20, 22 and 24 control the supplies of gas to the tank burner, toa pilot flame for preheating burner 14, and to radiant heater 16. Also,there is an open-shut valve 26 in the rear end of the fuel I supply line28 leading to pre-heating burner 28, valve 26, Y normally shut, beingopened by tensioning spring 29 as later detailed.

Referring to the right-hand portions of FIGURES 1 and 2, it will beobserved that pre-heating burner 14 is housed within a hood assembly 32attached on the front "of a transverse supporting plate 34. A flapbaflle 36 when cool, freezes hard. The invention is concerned primarilywith the material dispensing mechanism per se and in combination withthe radiant heater, and the interrelated control mechanisms detailedbelow.

As shown best in FIGURES l, 3, 4 and 5, a discharge chute 42 is pivotedat 44 to supporting plate 34, the chute lower end terminating in aroad-engaging shoe 46. A combined shoe gate and doctor blade 48 pivotedat 50 across the top of chute 42 is formed with a downwardly concavelower edge 49 so as to strike an arched top on the material extrudingtherefrom, it being understood that the gate may be closed against thelower rear wall of chute sufficiently to prevent any outflow of thethick, viscous plastic or it may be opened to varying degrees to providestripes of varying thickness. The viscosity of the plastic is sufficientso that no appreciable amount will flow beneath the slight concavity ofthe lower edge of the doctor blade when the latter is closed,particularly when the chute is lifted so that its inclination is slight.Combined gate and doctor blade 48 is swung open and closed by crank arms52 whose free ends are connected by a yoke 54 to the lower end of a rod56 attached at its upper end to a lever 58. Lever 58 has a pivotalsupport 60 on the side of casing 4 and a handle 62 at its rear end. Asshown in FIGURES l and 3, lever 58 is in an intermediate position, inwhich combined shoe gate and doctor blade 48 is closed and chute 42 islowered so that shoe 46 rests on the roadway. By raising handle 62clockwise from its intermediate position, rod 56 is forced downwardlyfrom its full-line position of FIG. 3, thereby swinging crank arms 52clockwise about pivot 50 so that the combined shoe gate and doctor blade48 is opened to varying degrees, as illustrated by the dash lines inFIG. 3, depending on how far the handle is raised.

When it is desired to cut off the fiow of striping material onto theroadway from chute 42, handle 62 is lowered to its intermediate positionso that rod 56 returns to its full-line position of FIG. 3, whereuponthe combined shoe gate 48 closes counter-clockwise about pivot (50against the lower side of chute 42. Since the combined shoe gate anddoctor blade 48 cannot swing counter-clockwise beyond its closedposition, further lifting of rod 56, caused by swinging lever 62downwardly from its intermediate position, swings chute 42 upwardlyabout pivot 44 to the position shown in broken lines in FIG. 3.

Tension spring 29, connected at its lower end to openshut valve 26, isattached at its upper end to the handle side of lever 58. In theintermediate and lower positions of lever handle 62, valve 26 is shutand pre-heating burner 14 is off. However, clockwise movement of leverhandle 62 from its intermediate position opens valve 26 and the gas fromburner 14, ignited by a pilot, preheats the road at the same time theplastic material is permitted to flow onto the road.

Hot plastic material from tank flows into chute 42 via-material outletpipe 64 and valve casing 66, the How being controlled by a valve 68pivoted at 70 to casing 66. Valve 68, which is capable of controllingthe flow of thick viscous liquids of molasses-like consistency, ispivoted at :72 to the lower end of a rod 74. The upper end of rod 74 isconnected to the forward end of a control lever 76 supported on pivot 78and having a handle 80 on its.

rear'end. Lowering and raising of handle 80 opens and closes molassesvalve 68 to varying degrees.

An apron 82, beneath which radiant burner 16 is .mounted, extendsrearwardly from plate 34, and is supported at its rear by braces 84connected to a bracket arm 86. A glass bead dispenser 88 is supported bypivots '90 on arm 86 and contains a rotary distributor mounted acompression spring engaged between the rear ends of arm 106 and a lever112 pivotally supported at its front end on dispenser 88. As shown inFIGURE 1, a link 114 is pivoted at its lower end 116 to lever 112 and atits upper end 118 to lever 88.

In operation, applicator 2 is pushed along a roadway R by handle 120.Shortly before a stripe is to be started, handle 62 is raised to theintermediate position shown in FIGURE 1 so as to lower chute 42 from itsdotted line position (FIGURE 3) to its full line position, wherein shoe46 rests on the road. Handle is then pushed down so as to open molassesvalve 68 enough to start the material down chute 42 which, along withoutlet pipe 64, valve casing 66, molasses valve 68, shoe 46 and gate 48,was pro-heated by the radiant heater 16. Molasses valve 68 is thentemporarily closed, and lever 62 is raised to its upper dotted lineposition (FIGURE 1) so as to open the combined shoe gate and doctorblade 48, press wheel 108 against the roadway and start pro-heatingburner 14. At this point, the operator starts pushing the applicatoralong, and re-opens molasses valve 68 sufficiently to permit acontinuous flow of material into the shoe, the molasses valve beingopened to greater or lesser degree to maintain a constant supply ofmaterial, depending on the width of the stripe and the speed ofpropulsion.

A few feet prior to the end of the line, molasses valve 68 is closed sothat most of the material in chute 42 and shoe 46 will run out by thetime the stripe is to be ended. At the end of the stripe, the rear end62 of lever 58 is swung down beyond its full line position (FIGURE 1) soas first to close the combined shoe gate and doctor blade 48 andsimultaneously shut off pre-heating burner 14. The first downward motionof the rear end of the lever relieves some of the pressure of spring 110on wheel 100. Further downward motion of the lever lifts chute 42upwardly while lifting the bead dispenser drive wheel 108 off theroadway. When chute 42 is lifted off the highway, the major part of itand shoe 46 are disposed comparatively close to radiant heater 16. Thusthe chute and related parts are thoroughly pre-heated prior to the startof a stripe, and they are kept well heated between striping operations.

The invention is not limited to the details described and illustratedherein, but is intended to cover all substitutions, modifications andequivalents within the scope of the following claims.

I claim:

1. In a stripe applicator for pavements, a tank adapted to containstripe-forming material, outlet means for said tank, a discharge chutehaving input and output ends, a pivot mounting said input end of saidchute adjacent the outlet means of the tank for receiving said materialtherefrom, the output end of said chute being vertically swingable aboutsaid pivot between lowered and raised positions, a gate for closing thechute, a pivot means pivotally mounting the gate on said chute adjacentthe output end thereof, a lever rigid with said gate and swingingtherewith about said pivot means, a control member movably mounted onsaid applicator and being movable between lower, intermediate and upperpositions, and means connecting said control member to the end of saidlever to swing the gate from open to closed position when said operatingmember is moved from said lower to said intermediate position andwhereby further raising of said control member from said intermediateposition to said upper position swings the output end of the chuteupwardly about said pivot from said lowered position to said raisedposition.

2. The combination claimed in claim 1 said gate comprising a platehaving a free edge remove from said fulcrum, said free edge beingconcave whereby to strike an arched top surface on the material issuingfrom the output end of the fulcrum.

3. In the combination claimed in claim 1, a pre-heating burner on saidapplicator disposed to blast a flame on the pavement in front of saidchute, a fuel supply conduit for said pre-heating burner, a controlvalve in said conduit, and means connecting said operating member andsaid control valve for opening the latter upon movement of saidoperating member from said intermediate position to said lower position.

References Cited in the file of this patent UNITED STATES PATENTSHollingshead Apr. 6, 1937 Lett May 13, 1941 Blankner May 13, 1947Middlestadt Dec. 11, 1951

